Automatic alarm.



PATENTED NOV. 20, 11906.

I. FILSON.

AUTOMATIC ALARM.

APPLICATION FILED FEB. a, 1905.

8. mutton Wihwaom UNITED STATES PATENT OFFICE.

' IRA FILSON, OF SPRINGFIELD, OHIO.

AUTOMATIC ALARM.-

Specification of Letters Patent.

Application filed February 8, 1905. Serial No. 2%.706-

fatented Nov. 20, 1906.

To all whom/it may concern:

Be it known that I, IRA FILsON, a citizen of the United States, residing at Springfield, in the county of Clark and State of Ohio, have invented certain new and useful Improvements in Automatic Alarms, of which the fol-' lowing is a specification, reference being had therein to the accompanying drawings.

This invention relates to automatic alarms, being designed primarily for use in connection with stoves, furnaces, or other heating apparatus employing gaseous fuel, and particu arly natural gas; where danger arises in case of a temporary failure of the fuel-supply, although the invention is capable of use in other connections.

The primary object of the invention is to provide an ap aratus which will give an alarm in case 0 any material interruption of the fuel-supply, so as to permit the taking of the necessary steps to prevent the escape of unburned gas in case "the fuel-supply isrestablished.

Other objects of the invention are to provide a simp e efiicient a paratus of this character which may be readily applied to a heating apparatus already in use, which .may be .readily adjusted to meet the varying conditions, and which may be controlled to render it operative or inoperative from different points either at the heating apparatus or at a distance therefrom.

To these and other ends my invention consists in certain novel features, which I Wlll now proceed to describe and will then particularly point out in the claims.

In the accompanying drawings, Figure l is, a perspective view illustrating an apparatus embodying my invention in one form, the same being shown applied to the smoke flue or pipe of a stove or furnace. Fig. 2 is a plan section of the same, taken above the apparatus proper. Fig. 3 is a vertical sectional view of the same, taken on the line me of Fig. 1 and looking in the direction of the arrows. Fig. 4 is a detail sectional view illustrating the connection of the bracket to the pipe.

Fig. 5 is a detail elevation of a portion of the pipe, showing the form of the aperture therein, the vane-bearing arm being shown in position therein and in transverse section; and Fig. 6 is a'perspective view of the locking slide or latch detached, by means of which the a aratus may be positively and mechanical y ocked in inoperative posltion. Referring to the construction chosen for purposes of illustration, which shows the ap paratus applied to the ordinary sheet-iron section adapted for insertion therein. In

this pipe there is formed an opening 2 in the wall thereof for the passage of the vanebearingarm 3, which is pivotally mounted in said opening. formed in any approved manner; but I prefer the construction shown, in which the opening 2 is enlarged at its lower part, as indicated at 4, and has extending upward from its lower margin a projection 5, formed of the sheet metal of the pipe. The opening 2 communicates at its upper end with a considerably larger opening 6 through the wall of the pipe. The arm 3, in the form of an inverted V in cross-section where it passes through the pipe, so as to straddle the projection 5, and its diverging arts 7 are of greater length than the pro ection and are cut away on each side, as indicated at 8, to straddle the wall of the pipe on which they rest as a fulcrum and prevent displacement of the arm in a longitudinal direction, theprojection 5 preventing lateral displacement. That portion of the arm 3 lying immediately outward from the inverted-V-shape portion 7 is of less Width than the upper part of the opening 2, as indicated at 9, so that the arm can 'be removed from the pipe through the upper end thereof by first moving the arm upward and inward until the part 9 thereof can be passed up through the upper part of the opening 2, thereby bringing the arm up into the larger opening 6, through which said arm and its counterweights may be readily passed in an upwardly-inclined direction. 1

The arm 3 is provided within the. pipe 1 with a vane 10 ofa diameter somewhat smaller than the internal diameter of the pipe. At its other end the arm 3 is counter- The connection may be weighted, and in the present instance I have shown the counterweighting as effected partly by a fixed counterweight 11 in the form of a block secured to the arm 3 and partly by an adjustable counterweight 12 in the form of a screw threaded in the block 11 and movable in the direction of the longitudinal axis of the arm, so as to adjust the relationship of the weights carried by the arm on the opposite sides of its pivot. Normally these weights are so adjusted that the vane is slightly heavier than the counterweighting,

I no

and the portion of the arm outside of the plpe tends to rise when the vane moves downward Within the pipe, the action of said counterweights being sufiicient to permit the vane to rise in the pipe when the products of combustion in the stove or furnace to which the pipe is connected pass through said pipe or when currents of heated air similarly pass through said pipe. The counterweights are of a si'z'e sufficiently small to permit them to pass through the opening 6.

13 hrdicatesa bracket on'the outside of the pipe 1' referebly in a position such as to covcr the opening 6' and prevent said opening from afiFe'c'ting' the draft of the stove or fur Irace or" ermitting the escape of the products of c'o'mhhstion. This bracket is preferably secured to the pipe in the manner shown in detail in Fig. 4, in which each end of the Brackets secured to the pipe by means of a naw-acre i4, extendin throu h an aperture in the pipe and having its head located inside the pipe, which is clamped between said head and a nut E6 on the body of the screw-bolt, a washer 17 being interposed between the head a d pi e, if desired. The bracket 13' is prcvided near each end! with a verticalopen-mouthed slot 18, by means of which it may be slipped down over the proj'e'cting ends of the bolts 14 and clamped in e-siti'on against the nuts 16 by means of nuts- 19', mounted on the bolts outside of the bracket. By r'eason' of this construction the bracket ma be readily applied to and removed from the bolts, it being sufiicient' to merely loosen the nuts 19 to permit the bracket to he slipped out by an upward movement or as readily replaced. The bracket has outwardly-extend ng arms 20', between the ends or which and above the arm 3 is stretch-ed a wire 21, of conducting material, preferably cop er, supported atits ends by insulating-bloc s 22, to which it is connected. This wire forms one contactterminal of an electric circuit 23, cornpr'i'sin a battery or othersou'rce of electricity 24 an Y an alarm 25, preferably in theform of an audihle an or gong. This circuit also preferably contains a switch 26, by means of which it may be opened or closed.

Inpraetice the si 'nal maybe located atarry desired pointa3s, or instance, in a bedroom located at aconsiderable distance from the stove or furnace Similarly the controlling switch 2 6 may be l oc'ate'd at any desired oint, althou h preferably its location will hear the a arm, so as to permit it to be shut ofl by breaking the circuit as soon as it has ac'com .lished its object by attractin attention. The other contactterminal o the circuit 23 is the arm 3", to which the circuitwire is connected in any suitable manner.

In the resent instance I have shown the I as orming art of the circuit, the wire en'ig connected t' ereto at 27 in any suitable manner, the arm 3 being of conducting material and being included in the circuit by reason of its contact With the pipe at its hearing thereon.

28 indicates a locking slide or latch for positively and mechanically holding the arm 3 in position such as to prevent its operating the alarm. This slide is mounted on the exe terior of the pipe 1, around which it slides transversely with respect to the arm 3, being guided in any suitable manner as, for instance, by a slot 29 in the slide and bolts 29*, secured to. the pipe. This slide is provided at one end with a projecting" ringsiece 30, by means of which it may be readily operated, its other end being provided with (H- vergingar'ms 31, which when thelatch is proje'cted past the arm 3- will ei'igag'e said arm from above and below, respectively, and will hold it fixed in inoperative position.

The operation of the apparatus is as fol lows, assuming that it is applied to a stove or furnace uslng natural gas as a fuel: As long as the gas-supply continues and is be ing consumed the heated products of combustion pass through the pipe and will! act upon the vane I0 so as to move the same upward and keep the arm 3 from contacting with the wire 21'. If 1 the supply of gas c'ease's only for a brief period and thenresurrres its flow and the stove or furnace is rovided with a filling of material heated y the gas, which fiHin will retain its heat for some time and we? reignite the gas if the flow begins again sufficiently soon, their the alarm will not operate, since the heated air passing through the pipewill act onthe vase is the same Inanner'asthe products-of com bastion when the gas is burning; but if the period of suspension or flow is too l'onto effect the reignition of the gas or if the s yes or furnace has no reignition me'ainsthen when the products of combustionor heated air cease to flow throu h the pipe the overweight of the vane wii cause that end 0! the arm to which it is attached to fall and the other end will rise, bringing the arm 3 into" contact with the wire 21. This will close the electric circuit and sound the elem, thereby giving notice of the danger from the flow of non-consumed gas. One mate rial advantage of the particular constfuc'ticrn shown is that since the arm 3 is so balanced as to be very sensitive, while the wire 21 is more or less resilient, the alarm is at first an interrupted one, the circuit being alternately closed and opened at successively de'ereasin intervals until it finally remains closed. is initial interrupted er'spesmodic action is in practice more effieient in attracting notice than a continuous alarm. As ai'ready stated, the alarm can be out o as soon as ithas accomplished its purpose by means of the switch 26'. The; same result can be obtained at the stove or furnace itself by means of the slide-28. This slide, however, is primarily intended to lock the arm 3 in inoperative position when the stove or furnace is not in useas, for instance, during the summer.

It will be seen that the structure is inexpensive and can be readily applied to the pipe of a stove or furnace already in place, and its application and removal are readily effected.

While the construction which I have illustrated and described is that which I prefer, it is obvious that modifications may be made without departing from the principle of my invention, and I therefore do not wish to be understood as limiting myself strictly to the precise details of construction hereinbefore described, and shown in the accompanying drawings. It is also obvious that the invention is capable of other applications and adapted for use in other c'onnections than the specific ones set forth.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, isv 1. The combination, with a support provided with a vane, an electric circuit comprising a source of electricity, an alarm and a fixed contact-terminal located in the pathof the arm, said arm constituting the other contact-terminal of said circuit, and means for positively and mechanically lockin said arm in inoperative position, substantia ly as described.

2. The combination, with a support, of a pivoted arm provided with a vane, an electric circuit comprising a source of electricity, an alarm, a circuit -controlling switch and a fixed contact-terminallocated in the path of the arm, said arm constituting the other contact-terminal of said circuit, and means for positively and mechanically lockin said arm in inoperative position, substantia ly asdescribed. I i

3. The combination, with the outlet-pi e of a stove or furnace, .of an arm pivota y sup orted thereon, extending through the describe 4. The combination, with the outlet-pi e of a stove or furnace, of an arm pivota y mounted thereon, extending through the wall thereof and provided with a vane within said pipe, a bracket mounted on said pipe and having arms, a wire of conducting material stretched between said bracket-arms in the path of the vane-bearing arm, and an electric circuit comprising a source of electricity and an alarm and havin its ends respectively connected to said wire and vane-bearing arm, substantially as described.

5. The combination, with a ipe-section having in its wall an a erture en arged at its lower end and provi ed withan upwardlyextending projection, and a second aperture of larger diameter communicating with the restricted portion of said first-mentioned aperture, of an arm-provided with a vane at one end and a counterbalance at the other end, the latter of less size than the larger aperturein the pipe, said arm being of mverted-V shape in cross-section at its fulcrumpoint, with its lateral portions cut away to straddle the pipe-wall, and of a Width outward from its fulcrum portion to pass through the restricted ortion of the opening in the pipe, substantia y as described.

In testimony whereof I affix my signature in presence of two witnesses.

, IRA FILSON.

Witnesses:

IRVINE MILLER, J. F. KrroHEN. 

